Improvement in harrow-teeth



okq New tluiml ANDREW PATTERSON, OF BIRMINGHAM, PENNSYLVANIA.

' Letters Patent No. 83,656, dated November 3, 1868.

IMPROVEMENT HARROW-TEETH.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern:

Be it known that I, ANDREW PATTERSON, of the borough of Birmingham, Allegheny coimty, State of Pennsylvania, have invented certain new and useful Improvements in the Manner of Making and Attaching Hzu-row-Teeth; and I hereby declare that the following is a full, clear, and exact description thereof, reference being bad to the accompanying drawings, and to the letters of explanation marked thereon, which form part of this specification.

I make my improved tooth of angle-iron or steel, and insert it through a hole in the harrow-fi-ame, in a manner similar to that in which the ordinary solid tooth is inserted, except that, to firmly secure it in any required position, I insert a wedge or key, which the inner angle of the tooth and the adjacent part of the hole through which the tooth is inserted.

. A most convenient mode of making these teeth is to take previously-rolled angle-iron or steel, of suitable size, cut it into proper lengths to form a single tooth, (see Figure 1,) and then out off the corners,

(b b, fig. l,) when the tooth a is ready for use. Its proper application to the ha1row fra1ne will be at once obvious, and is fully illustrated by the drawings, of which- 1 i Figure 2 is a perspective, showing a part of the frame, d, with a tooth, a, inserted and held in place by the wedge c.

Figure 3 is a horizontal section through the frame- 7 tooth and wedge, like letters indicating the same parts as in fig. 2. I

It is proper to say that it is not absolutely necessary that the bar from which the teeth are out should be rolled angular; it may be rolled flat, and the teeth out in lengths, pointed, and then swaged into shape between dies. It is perhaps better to give the teeth a slightly sharper angle than ordinary angledron usually has. I prefer to give the sides an angle of about seventy degrees, and for teeth of one inch wide, sides about and the frequent scarfing of the corners to make them. keep their place. My tooth can be readily adjusted to any position by any common farm-laborer. The wedges may be either metal or hard wood, of slight taper, and should be driven from the top downwards. The holes for the teeth should be the smallest through which the teeth can be conveniently driven with moderate force.

I am aware that cultivator-teeth have been fastened in their frame in a manner not diifering in principle fiom that shown in this case. They were, however, permanently secured in one position. 1 do not, therefore, claim broadly fastening harrow-teeth with a Wedge.

I claim, as an improved article of manufacture- An angular iron orsteel barrow-tooth, made substantially as shown and described.

' ANDREW PATTERSON. Witnesses:

A. B. STEVENSON, J OHN G. s'rnvnnson. 

